Electronics Forum | Fri Jan 22 16:03:17 EST 2021 | SMTA-64387124
Does anyone see any issues in mixing SMD and NSMD pads within one BGA footprint. We have high current pads which we want to make SMD and the other signal pads to be NSMD
Electronics Forum | Fri Jan 29 16:17:13 EST 2021 | donnie15
The impact is low on larger pitches and pad sizes. as things get to the .4mm pitch the pad differences start affect your ball size and yields. The trace size going into the pads and the solder mask relief can cause some odd shaped pads with signif
Electronics Forum | Tue Feb 09 16:53:06 EST 2021 | SMTA-64387083
The size of the pad changes among the two. A solder mask defined pad will always be larger than a copper defined by your mask expansion setting. This will affect paste volume, if your standard paste aperture is designed for copper defined pads you m
Electronics Forum | Fri Dec 10 08:42:37 EST 2004 | mattkehoe
We had some bad experiences trying to work with soldermask defined BGA pads. If the opening in the soldermask is right to the edge of the copper/pad without a space it can leave reside on the pad and nothing will stick to it. See http://www.sipad.com
Electronics Forum | Tue May 21 07:46:58 EDT 2024 | tommy_magyar
Michal, Overprinting is the extension of the stencil aperture over the solder mask, to enable a bigger volume of solder paste on the pad, therefore bigger volume of the solder joint after reflow. https://youtu.be/WAIm-6BSaiQ?si=UMp9WSFal3vXFp8F as
Electronics Forum | Fri May 17 17:57:10 EDT 2024 | yannick_herzog
Hello, We have problems with insufficient solder volume on a component. To solve this problem, we want to add more paste to the component. We have two options for this: 1. run a stencil with a step to achieve the required volume. 2. overprinting
Electronics Forum | Tue Mar 25 13:55:05 EDT 2014 | horchak
Ok lets put it this way. If the PCB house used a high quality mask and properly applied it to a properly cleaned surface and properly cured it, then as Dave stated above there are only two things that can destroy it. Excessive heat and overly aggress
Electronics Forum | Wed Dec 08 19:50:34 EST 2004 | shen_zte
can anyone tell me the benifit of the solder mask onto pad(part) or pad defined by solder mask?and how to excute the SMT process ? thanks.
Electronics Forum | Thu Dec 09 07:46:42 EST 2004 | davef
We did this for BGA pads, but have not thought about other types. So, this may or may not apply for those. Pad defined by:||Advantages||Disadvantages Non-solder mask||No point-of-stress concentration at edge mask and solder ball||Smaller pads have
Electronics Forum | Thu Sep 03 22:03:32 EDT 2020 | SMTA-64386139
Both conditions are acceptable for this bottom brazed flat pack package. The solder coverage must be within 0.070 inch of the lead/package interface per MIL-PRF-38535, paragraph A3.5.6.3.4.a. While that requirement could allow for a gold gap near t
